纸制口罩和外科口罩几乎无法阻止烟雾颗粒。

#清新十周年# 当细颗粒物污染水平极高时，我该怎么做才能减少暴露？不要依赖防尘口罩进行保护。纸制防尘口罩的设计是为了阻止大颗粒物的，如锯末。这些口罩不能阻止PM2.5等细颗粒物进入您的肺部。围巾或头巾也无法提供保护。随弃式防护口罩，也称N-95口罩，如果您正确佩戴，在室外可起到作用。

What can I do to reduce my exposure to fine particle pollution when levels are extremely high?  Do not rely on dust masks for protection. Paper "dust" masks are designed to trap large particles, such as sawdust. These masks will not protect your lungs from small particles such as PM2.5. Scarves or bandanas won’t help either.  If you wear them correctly, disposable respirators known as N-95 respirators will help when you are outdoors. #freshten#